Apparatus for Pivoting a Platform of a Treadmill

ABSTRACT

Disclosed is an apparatus for pivoting a platform on a base of a treadmill. The apparatus includes two front tracks secured to the base, two front casters movable in the front tracks, an axle connected to the front casters, a sleeve for receiving the axle, two front rockers each including an end pivotally connected to the platform and another end connected to an end of the sleeve, a motor supported on the platform, an extensible element including an end operatively connected to the motor and another end connected to sleeve, two rear tracks secured to the base, two rear casters movable in the rear tracks, two rear rockers each including an end pivotally connected to the platform and another end connected to a related one of the rear casters, and two connectors each for connecting a related one of the front rockers to a related one of the rear rockers.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a treadmill and, more particularly, toan apparatus for pivoting a platform relative to a base of a treadmill.

2. Related Prior Art

A conventional treadmill includes a base, a platform and a conventionalapparatus for pivoting the platform relative to the base. Theconventional pivoting apparatus lifts a rear end of the platform forstorage and lifts a front end of the platform for imitation of an uphillslope to be encountered by a runner. The operation of the conventionalpivoting apparatus is not smooth. In addition, the structure of theconventional pivoting apparatus is weak and vulnerable to deformation,fracture or even breakage, and this is dangerous for the runner.

The present invention is therefore intended to obviate or at leastalleviate the problems encountered in prior art.

SUMMARY OF INVENTION

It is the primary objective of the present invention to provide areliable apparatus for pivoting a platform relative to a base of atreadmill.

To achieve the foregoing objectives, the apparatus includes two fronttracks secured to the base, two front casters each movably located in arelated one of the front tracks, an axle connected to the front casters,a sleeve for receiving the axle, two front rockers each including an endpivotally connected to the platform and another end connected to arelated end of the sleeve, a motor supported on the platform, anextensible element including an end operatively connected to the motorand another end pivotally connected to sleeve, two rear tracks securedto the base, two rear casters each movably located in a related one ofthe rear tracks, two rear rockers each including an end pivotallyconnected to the platform and another end connected to a related one ofthe rear casters, and two connectors each including an end pivotallyconnected to a related one of the front rockers and another endpivotally connected to a related one of the rear rockers.

In an aspect, the apparatus may further include a sleeve located betweenand connected to the rear tracks.

In another aspect, the apparatus may further include a rod and apneumatic cylinder. The rod is connected to the rear rockers. Thepneumatic cylinder includes an end pivotally connected to the platformand another end pivotally connected to the rod.

Other objectives, advantages and features of the present invention willbe apparent from the following description referring to the attacheddrawings.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be described via detailed illustration of thepreferred embodiment referring to the drawings wherein:

FIG. 1 is a perspective view of a treadmill equipped with an apparatusfor pivoting a platform relative to a base according to the preferredembodiment of the present invention;

FIG. 2 is a perspective view of the pivoting apparatus shown in FIG. 1;

FIG. 3 is a side view of the pivoting apparatus shown in FIG. 1;

FIG. 4 is a perspective view of the pivoting apparatus in anotherposition than shown in FIG. 2;

FIG. 5 is a side view of the pivoting apparatus shown in FIG. 4;

FIG. 6 is a perspective view of the pivoting apparatus in anotherposition than shown in FIG. 4; and

FIG. 7 is a side view of the pivoting apparatus shown in FIG. 6.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring to FIGS. 1 to 3, a treadmill includes a base 10, a platform 20and an apparatus 100 for pivoting the platform 20 relative to the base10 according to the preferred embodiment of the present invention. Thebase 10 is in the form of a rectangular frame. Two posts 11 are providedon the base 10.

The platform 20 includes two lateral beams 21, front and rear rollers 22located between and connected to the lateral beams 21, a primary plate25 supported on the lateral beams 21, a belt 26 in the form of a looparound the front and rollers 22 and the primary plate 25, two wheels 27each attached to a related one of the lateral beams 21, a secondaryplate 28 supported thereon, and a mount 29 supported thereon. Theplatform 20 includes a front end 23 and a rear end 24. The lateral beams21 extend between the front end 23 and the rear end 24 of the platform20. The primary plate 25 is located between the lateral beams 21 and thefront and rear rollers 22. The belt 26 includes an upper section movablysupported on the primary plate 25. The secondary plate 28 is supportedby two crossbars located between and connected to the lateral beams 21.The mount 29 includes a lower end connected to one of the crossbars.

A motor 30 is supported on the secondary plate 28. A wheel or pulley 32is connected to the front roller 22. A bet 31 is in the form of a looparound the mandrel of the motor 30 and the pulley 32. Thus, the motor 30is operable to drive the belt 26 through the belt 31, the pulley 32 andthe front roller 22.

The pivoting apparatus 100 includes a motor 33 and a linkage 40. Thelinkage 40 includes a sleeve 41, an axle 42, two front rockers 43, fourlugs 44, two front casters 45, two front tracks 46, two connectors 47,two rear tracks 50, two rear rockers 51, a rod 52, two rear casters 53,a sleeve 54 and a pneumatic or hydraulic cylinder 56. Each of the fronttracks 46 is secured to a related lateral bar of the base 10 while therear tracks 50 are secured to a crossbar connected to the lateral barsof the base 10.

The lugs 44 are connected to the platform 20 and, more particularly, toa crossbar located between and connected to the lateral beams 21. Eachof the front rockers 43 includes an end pivotally connected to a relatedone of the lugs 44 and another end connected to a related end of thesleeve 41. The axle 42 is rotationally inserted through the sleeve 41,with two ends of the axle 42 located outside the sleeve 41. The frontcasters 45 may be bearings. Each of the front casters 45 is rotationallyconnected to a related one of the ends of the axle 42 and movablylocated in a related one of the front tracks 46. Each of the connectors47 includes an end pivotally connected to a related one of the frontrockers 43 and another end pivotally connected to a related one of thetracks 50.

Each of the rear rockers 51 includes an end pivotally connected to arelated one of the lugs 44. The rod 52 is located between the rearrockers 51, with two reduced ends of the rod 52 inserted through anaperture defined in the end of a related one of the rear rockers 51. Therear casters 53 may be bearings. Each of the rear casters 53 isrotationally connected to another end of a related one of the rearrockers 51 and movably located in a related one of the rear tracks 50.The pneumatic cylinder 56 includes an end pivotally connected to the rod52 and another end pivotally connected to the platform 20 and, moreparticularly, to a crossbar located between and connected to the lateralbeams 21.

The sleeve 54 is secured to the tracks 50. Each of the wheels 55 isconnected to a related end of an axle inserted through the sleeve 54.

There is provided an extensible device 34. The extensible device 34includes a screw connected to the mandrel of the motor 33 and a tubepivotally connected to the sleeve 41. The screw is driven in a screwhole defined in the tube. Thus, the motor 33 is operable to spin thescrew relative to the tube so that the extensible 34 can be extended orshrunk.

Referring to FIGS. 2 and 3, a rear end of the platform 20 is manuallylifted for storage of the treadmill. The pneumatic cylinder 56 is usefulin the lifting of the rear end of the platform 20. The wheels 55 areuseful for transportation of the treadmill when the rear end of theplatform 20 is lifted.

Referring to FIGS. 4 and 5, the rear end of the platform 20 is manuallylowered for use of the treadmill. The pneumatic cylinder 56 is useful inbuffering the lowering of the rear end of the platform 20. The frontrockers 43 are pivotally toward the front end 23 of the platform 20 asthe front casters 45 are moved toward the front ends of the front tracks46. The rear rockers 51 are pivotally toward the rear end 24 of theplatform 20 as the rear casters 53 are moved toward the rear ends of therear tracks 50. That is, the front rockers 43 and the rear rockers 51are pivoted away from each other. The connectors 47 are lowered.

Referring to FIGS. 6 and 7, the motor 33 is operated to extend theextensible device 34. The front rockers 43 are pivotally toward the rearend 24 of the platform 20 as the front casters 45 are moved toward therear ends of the front tracks 46. The rear rockers 51 are pivotallytoward the front end 23 of the platform 20 as the rear casters 53 aremoved toward the front ends of the rear tracks 50. That is, the frontrockers 43 and the rear rockers 51 are pivoted toward each other. Theconnectors 47 are lifted.

The operation of the linkage 40 is smooth since the front casters 45 aresmoothly moved in the front tracks 46 while the rear casters 53 aresmoothly moved in the rear tracks 50. Furthermore, the structure of thelinkage 40 is strong for the use of the sleeve 41, the connectors 47 andthe rod 52.

The present invention has been described via the detailed illustrationof the preferred embodiment. Those skilled in the art can derivevariations from the preferred embodiment without departing from thescope of the present invention. Therefore, the preferred embodimentshall not limit the scope of the present invention defined in theclaims.

1. An apparatus for pivoting a platform relative to a base of atreadmill, the apparatus including: two front tracks secured to thebase; two front casters each movably located in a related one of thefront tracks; an axle connected to the front casters; a sleeve forreceiving the axle; two front rockers each including an end pivotallyconnected to the platform and another end connected to a related end ofthe sleeve; a motor supported on the platform; an extensible deviceincluding an end operatively connected to the motor and another endpivotally connected to sleeve; two rear tracks secured to the base; tworear casters each movably located in a related one of the rear tracks;two rear rockers each including an end pivotally connected to theplatform and another end connected to a related one of the rear casters;and two connectors each including an end pivotally connected to arelated one of the front rockers and another end pivotally connected toa related one of the rear rockers.
 2. The apparatus according to claim1, further including a sleeve located between and connected to the reartracks.
 3. The apparatus according to claim 1, further including: a rodconnected to the rear rockers; and a pneumatic cylinder including an endpivotally connected to the platform and another end pivotally connectedto the rod.